A combined numerical model is proposed in order to solve ablation and denudation under high temperature and high pressure. Vortex method is used for simulating vorticity field and pressure distribution; a three-equation model is used for resolving the ablation mass loss; and a trajectory model is adopted for solving the motion of denudated particles. Compared with the flow past an ablating cylinder with the same Re number and ablation condition, the ablation effect on the sphere-conic is more significant and the vorticity contour turned to an asymmetric structure earlier; the particle traces are no longer symmetric, and the particles distribution become unorganized; the linear momentum of the ablating sphere-conic become larger than the non-ablating one; This simulation may offer numerical references to ablation experiments on thermal protection materials.